Process for breaking emulsions



Patented Jan. 15, 1935 PATENT OFFICE-Q 1,987,870 raoosss FOR BREAKING EMULSIONS Charles J. Robinson, Claremont, C'alifi, assignor to L. Blake-Smith, San Francisco, Calif.

No Drawing. Application March 18,1933,

Serial No. 661,586

18 Claims.

The object' of myoinvention is to. provide a method for rapidly and certainly resolving: emul sions of. oiliand waterinto their-constituents, the:

invention being applicable to the. type i emul,

sion in whichzwater is thedisperse phase. (known oil is the disperse phase (known as oil-in-water emulsion). V

example of the; first: named type is the emulsion often produced in bringing crude petroleumitozthez surface, this-type of" emulsion having.

oil" as. the continuous: phase: and. therefore being miscible with oil.

An. example of thewsecond, named type is the emulsiont often produced in treating petroleum lubricating oils,. first with acid and then with alkali: and water; This type of emulsion has water asthe continuous phase and'therefore is miscible With? water.

In a copending application filed May 21, 1932 under the title. Process for resolving emulsions 7 pending application are of highly varied nature chemically, their usefulnessbeing measured primarily by the relation of their adhesion tension with the disperse liquid to their adhesion tension with the continuous liquid, modified byarequirement for. such relatively high specific gravity as will cause the solid to pass rapidly through the emulsion mass and by a requirement for. such degree of. hardness as will prevent undue wearingaway of. the hard granulesby. attrition.

In applying the process of the copending applicationI customarily. used the agent in the form of a rather coarse powder, for instance such as would pass a lo-mesh screen and be retained on a GO-mesh, any fine dust which might adhere to these grains being washed away. In repeated trials of this process I observed that while, in many cases, resolution of the emulsion would start as soon as agitation of the solid) with the emulsion began, in other cases resolution would not occur at any useful rate until agitation had been continued forsomelittle. time, I, also observed that in the cases where resolution was slow in starting it would continue to accelerate for a considerable time until it reached a rapid rate, andthat in long continued treatments inwhich all the solid matter was retained in the treatingvessel and contacted with a flow of emulsion, the rate of resolution would reach an apex after which-it would gradually or rapidly decline and sometimes entirely cease. as water-in.- oil emulsion) and tothe type in which Ininvestigating' these observations I discov ered that the acceleration of the resolution-rate: is due to the formation, by attrition, of a small. proportion of colloidal or at least of very 'finely divided solid treating material, and that" the: rate of resolution is accelerated until this finely divided solid reaches an optimumproportion to the mass of emulsion in which it'is suspended; and that when this optimum proportion is over reached the rate ofiresolution isdecelerated and, if carried sufiiciently far; the resolution isifinally terminated.

Reasoning from these observations, I further discovered that by-initially addingto: the emulsion, with the' coarsely powdered" solid, a small quantity of the same or a similar. agent reduced; to a very fine state of subdivision, the" resolution effect could be. produced immediately and at. its maximum rate; also that the rate of resolution could be materially increased by using with: the;

finely divided'agent a coarser agent thaniI had originally contemplated; also that theuse. of the: finely divided agent enables me to utilize, in; coarse grains, solids having a loweradhesion tension relation than I had used-in theprocess of the; copending application; also that the proportion offines can be controlled in the course of along continued treatment and canbe maintainediatorrnear the optimum by the applicationof a simple visual test; all of which matterswill bev fully'set forth hereinafter.

The process'of the present invention consists: of the following steps? (1) selection of the:treating material or combination of' materials most suitable for the particular emulsion to be treated; (2) sizing of the treating materialor materials; (3) proportioning of the coarse and fine material to the body of emulsion; (4) maintaining contact between the emulsionbody and the. solids by any. one of severalwell known methods; (5') maintaining and controlling the proportional? finely divided solids in the mass; (6) separating the. solids from the resolution products, and (7) separating the resolution products fromv each other.

(1) Selection of treating materials 01 combina tions of materials The essential requirements of suitabletreating materials are: (a) lack of any appreciable chem-1 ical reactivity or solubility with any constituent: of the emulsion; (b) adhesiontension with the? liquid of. the disperse phase greater than the. adhesion tensionwith the liquid of the continue ousphase; (a) specific 'gravitymaterially difliere cut from that of the emulsion, i. e., heavier than its heaviest constituent or lighter than its lightest constituent, according to. the method of application. An additional'requirement for only the coarse treating agent is such degree of hardness as will prevent undue conversion of coarse intofine particles by attrition in long continued treat ments.

Lack of chemical reactivity and solubility is a requisite for the reason that the treatment herein described depends purely on surface phenomena and the consumption of the treating agents is to be avoided. In avoiding the consumption of the treating agent, the initial charge of agent is caused to maintain its treating efficiency over Very :long periods of continuous treatment, extending intomonths or until thecoarse particles become too much reduced in size byattrition or the fine particles are lost by physical wastage. It is also a requisite in that, to maintain the treatment at an even rate over long periods, the condition of the surfaces of the solid particles should not be changed by chemical action. The requirement for lack of chemical reactivity and solubility extends to'the fine as well as the coarse agent, as while the finely divided. zeolites and bentonite used by Brown 8; Meinzer Patent No. 1,911,727 will function in the same manner as my fine agent in some cases and for a limited time, they rapidly, become inert and cease to function and. also are practically impossible to separate from the resolution products for reuse; so that in practice they must constantly be supplied to the system. Further, as the agents are to be kept in use for long periods, it will be obvious that they must be substantially insoluble in any of the emulsion constituents.

The adhesion tension requirement for the coarse solid is materially less rigid than that set forth in the copendingapplication, and a useful and valuable result maybe obtained with any material having the other requirements herein set forth together with an adhesion tension with the dispersed liquid materially greater than the adhesion tension with the continuous liquid. The adhesion tension relation may be measured in the manner set forth in the copending application and reproduced in a later paragraph hereof under the heading Method of measuring adhesion tension relations.

The suitability of the material may also be determined by a simpler test. Portions of the two constituents of the emulsion, e. g., water and clear hydrocarbon oil, are both poured into a test-tube. A sample, one or two grams, of the solid agent, powdered relatively fine, perhaps between 50 and mesh, is added to the liquids, and the mixture shaken vigorously for a minute or two. On standing, the powder settles to the bottom, but will be coated with that one of the two liquids for which it has the greater adhesion tension. If the two liquids are a hydrocarbon oil and water, and the solid has a greater adhesion tension for the oil than for water, it will be filmed with oil even after it has settled into the water, andthis fact can readilybe observedby visual examination of the powder. There will also be a marked tendency for such a powder to remain at the oil-water interface instead of settling into the water. On the other hand, if the powder has a markedly greater adhesion tension for water than for oil, it will settle rapidly through the interface, and waetr will soon displace any oil from those particles which might have momentarily'been wet with oil: so that the powder will lie at the bottom of the test-tube practically free from oil.

Wherethe formal adhesion tension test hereinafter described is applied, the relation of the adhesion tensions should not be less than 1.5 to 1.0.

For reasons hereinafter stated, the adhesion tension requirement for the fine solid is as severe as that set forth in the copending application, and when the formal adhesion tension test is applied the relation of the adhesion tensions should not be materially less than 2.5 to 1.0.

It has been found in practice, however, that where the fine solids result from the mutual abrasion of the coarse solids, a satisfactory result in the resolution of the emulsion is produced even though the coarse material from which these fines are produced has an adhesion tension relation not greater than 1.5 to 1.0.

The simpler test described above may be applied somewhat more rigidly for selection of a suitable fine solid, by using a finer powder, say between 100 and mesh, and selecting only such kinds, of materials as pass freely through the interface from oil to water.

' The specific gravity requirement is based on the fact that the methods of application hereinafter described all function by reason of a gravity effect; that is to say, the coarse particles of agent are removed from their normal position (above or below the emulsion body) to an opposed position, from which they return under the influence of gravitation, contacting the dispersed particles during this return movement. As the agglomeration of the dispersed particles into separable masses is a function of the number of contacts so produced, the treating efiiciency of the agent will, other things being equal, vary directly as the gravity difference between the agent and the emulsion.

The most suitable treating agent will therefore be an insoluble, nonreactive solid body having the highest available adhesion tension for the liquid of the disperse phase together with the highest specific gravity difference and, in the case of the coarse agent, the greatest hardness. In the case of the finely divided agent there is no requirement for hardness.

As illustrative of materials suitable for use in this process, and without limiting myself thereby, I name the following:

For the treatment of water-in-oil emulsions with solid agents heavier than water: coarse agent-hematite (hard varieties) martite, garnet, hornblende (massive), magnetite, pyroxene, quartz, glass, alundum, corundum; fine agentr any of the above, also hematite (soft varieties) and limonite.

For the treatment of oil-in-water emulsions with solid agents lighter than the oil constituent: coarse agent-wood, cork, pumice, sepiolite, leather, all reduced to fragments or pellets of suitable size and preferably oil-wetted before use; fine agentfine sawdust (preferably hardwood), cork dust, coke dust, coal dust (preferably cannel coal), phenol-formaldehyde condensation products, and hard rubber.

These agents may be used singly or in intermixture, with due regard to size and weight requirements.

(2) Sizing of the treating material The function of the coarse particles in this process is to agglomerate into drops or masses the minute particles of dispersed liquid which have ness.

nesvysvo been':c0ntacted: byv thei finest I The r function:v of th'e fine.particlesrotzsolidiisto setliup arrincipient inversionwofithe emulsion: which; beingszarrested at the point of reversal, effectively liberatesithe dispersedwliquidiparticles:from the forcesxlwhateve'rithey may be) which hold them .inthe emul-i sified form. I r r i l For reasons alreadg'r given,m ita isadesirablea that the: coarse particles.shouldrgravitate throughotlie emulsionum'ass atithe highest speedy and;.I1there:-' fore reduce the coarsesagentto such sizeothatthe weight of zthe particle will beariaz-higl'r relation to it'sa"exposedu-lsurfac .Eiizes. passing: a; v5:.rnesh screen and iretairredi. ,ll zrimeshliformrazsuitable range wherathe Fspecificmgravityu of :the solid is from 6:0 to" 4.0; butifor: lighter solidsieven much larger sizes arelidesir-able, and are; permissibleiin all casess: "Where: the emulsion tobe treated is extremely viscous, theisizeit of thescoarseyparticles may be increasedw 1 w r a As the: fines-particles act :as an ;invertingragent, it: is desirable torhaverthem. 62413058117118 greatest possible amount ofisurfacd:andziforrthis reason I reducekthem'. toalstate: tof rvery considerable finea Preferably1 these-f particlesilshoul'dl all pass through a 100-mesh;screen;.:in1 order to" produce aminitially rapid: action; but iti'may bemomerved that unless-the material 10f these particles: is 'very hard;theywi1l rap-id1y be ground :to a -much' finer condition by attrition-between theymore-r rapidly moving coarse-grains; I

H (3) Rroportioningl coarse and fine Material The optimumuamount of. coarse "material: will vary 1 over a wide range; dependingvon :the: physi: caFmethods empl-oyed in effecting the; movement of T the solid through: the emulsion. Inzmethods which employ the velocity of the emulsiorustream to lift and distribute Ethe solids, tha chargea will be limited to the quantitylwhich can beeffectivee ly lifted and'distributed byathesavailable velocity, the" maximum J charge increasing; as r the specific gravity decreases.- Int methods-.whichamechanif cally raise'or lower the solid andrpermititfto;re.-

turn-to a positionlof rest, theoptimum charges is that at whichthe increase. ineffectiveness due to increased surface is balanced: by the decreased amount 'of emulsion retained imthe treating: ves sel-z A's illustrative only, the chargeninl apparatus using 1 velocity methods; may be .of i the order 10f two pounds oi coarser solidsper gallonoil emule sion; while in methodsxinawhich the. solidis moved mechanically the charge may be double that amount; s T 7 V The initial-:dosage ofxfines ia a somewhat deli? cat'e matter' and at present I knowe of no. wayto determine it other than by 'empirical experiment with the particularemulsion torbefresolved'; add

(4) Producing cndinaintaining contact In order; to: produce resolution-of; emulsion with the agents describedrthe, finasolids must be kept in suspension in:. the emulsion! and; the. coarse solids; musti. bee maintained in; rapid; movement throughiithe emulsion: body: This movement; witht'simultaneous 7 suspension of the fines; i may be pro'ducedainzmanyl different types of" apparatusgaswfor instance: by: means. of: a flow of air orrgas; asidescribed" inthezpatentito G. Meine zer, No. 1;9l1;8:40; by: means of l a pulsating: flow of'iemulsiomas describedlin the patent'to G. H: Meinzer; No; 1,8873%; by 'means, of a rotating vessel -having lifting ort depressing vanes asde-z scribed. inx the: application. of William: E. Van lioenenyserialrNo. 612,847; filed May 21, 1932, While I: prefer the latterz-operation as producing a travelofithe coarsesolids-gthrough the emulsion bodyrinronly oneidirection, andzthat the direction inz whichfther dispersephase moves to join an agglomeratedbody oicthe'disperseliquid, I claim nosinvention in; this present. application, in methodtoffcontacting the; solid with the liquid, and may. use: any known or preferredapparatus for. that. purpose;

(5') Controlling the proportion or fines.

Aswbefore stated; the finely divided solidtmust he"; 'considered. as; an emulsion, inverting agent, tending: to. produce: an emulsion of the type the reverseiofgthatbeing treated; The resolving effect of the agent increases with its adhesion tension',jwith',-the.liquid of the disperse phase, but H foran'ygiven material isla functicn-of the extent of: exposed: surface: rather than of the actual weight OfTfillGSOlid present. The weight: remain-,- ingaconstanti the surface exposure maybe increased; by-finergrinding of the solid, such as will. take place by; attritionbetween the coarser grains, while the weight. of fines present may be: increased by mutual attrition of the coarse grains and, in instancesavhere finely divided claysand shales; are present in 1 the emulsion, by the:passage-of these bodiesinto lthe water layer. Qnathemther hand the weight may be decreased by physicalzloss-of fines entrained in the oil product; wheretheyare invisible but willbe shown inza centrifuge test, and 0 especially in the waste water; where they are plainly visible.

In: every; continuous treatment and resolution of s. emulsion the initialv product: is a mixture of oil: andiwater which will separate-by gravitation intolsharply defined layers, andsuch layers are maintainedqinxthe treating vesselioifiin a separating-xvessel; or both; The water produced by resolution s is-a 1 waste product and is withdrawn, the oil being passed.- to storage or: to a secondary settling vessel where traces of free water may subside.- g

Orr account of" their rapid sedimentation it is usually possible to retain the coarse solids-in the treating vessel, but in all types of apparatus having' a; separate settling vessel; a portion of the tines will be carried out of thetreating vessel in suspension in the water, forming a sludgeor slime in ,the' bottom of, the. settling vessel. The first step, in maintaining-the optimum proportion of fines in the treating vessel is toreturn, all or the. requisite part of this sludgeto the treating vessel; It is ofisuch consistency as to be readily handled'through a pumping" means and the return withwthe sludge of i a moderate amount of water is seldom harmful and usually beneficial to the, treatment.

The proportiomot fines inthe treating vessel isecejntrolled'by withdrawing or discarding small amountsot this sludge iithe proportion becomes excessive; and by adding :newfines to the returned sludge if the proportion becomes too small. As there is seldom an actual loss of fines the requirement is usually for a reduction in the quantity as the fines grind to a smaller rize or increase in quantity in the manner above stated.

Any departure from the optimum dose of fines will be indicated by the failure to obtain complete resolution of the emulsion, as indicated by the centrifuge out. This indication, however, does not show the direction in which the optimum is departed from. Such information may be had from the appearance of the water layer, drawn from a medial point in the treating vessel or separator as the case may be, in a manner which varies with the type of emulsion being treated.

If the emulsion is of the usual water in-oil type, an excessive amount of fines will produce a material quantity of inverted or oil-in-water emulsion, which will be manifest in the water layer as fioating webs or films consisting of oil droplets surrounded by colloidal solids. If the separated water is entirely clear, the proportion for rapid and complete resolution is indicated by a slight turbidity in the separated water due to colloidal fines, with perhaps a trace of inverted emulsion. The spread of concentration of fines through which satisfactory results canbeachieved is sufficiently broad to make control practically feasible.

If the emulsion being treated is 'of the oil-inwater type, an entirely different set of indications is obtained. The partial resolution of an emulsion of this type liberates a portion of theoil in a water-free condition, or in a condition where it contains only such relatively large drops as will readily separate on standing. The appearance in the oil delivery of traces of water-in-oil emulsion is a definite indication of the presence of an excessive amount of fines in the mass under treatment. In the other direction, if the water draw shows more than a trace of oil being carried out, either the apparatus is being overfed and worked beyond its capacity or the proportion of fines is too small. If the feed rate is that at which the apparatus has normally been working on the same material, it is safe to assume that the dose of fines is too small, but if a normal operating rate is not available for comparison, the feed should temporarily be reduced and, if this reduced rate of treatment does not correct the difficulty, the proportion of fines should be increased. As this determination is slow and causes some loss of throughput, it is desirable to carry a faint trace of inverted (water-in-oil) emulsion in the oil delivery, which will indicate the optimum dosage of fines, and this trace may be so faint as to be visible only as a line in a centrifuge cut and not evident in the oil itself.

(6) Separating the solids from the resolution products and separating the resolution products from each other These two steps are functionally distinct but as they occur simultaneously, they cannot be separately described.

The coarse solids, because of their high relation of weight to surface, pass readily through the emulsion mass and through any separated layers of resolution products to their position of rest, and their separation offers no difliculty.

This is not true of the fines, which must be dispersed in the continuous liquid in order to exercise their inverting effect on the dispersed liquid particles and must pass into an agglomerated layer of the dispersed liquid in order that they may remain wetted with the liquid of the dispersed phase. From this agglomerated layer they must then be withdrawn and returned to the system.

To illustrate by example of the typical waterin-oil emulsion, which in progress of resolution forms a layer of water below a layer of oil containing more or less emulsion yet to be resolved. The coarse solids, being lifted in any manner from their position of rest at the bottom of the water layer, pass through the layer of oil, accumulating therefrom water droplets, and return to the water layer where thesedroplets are added to the agglomerated mass. Thefine solids, however, must be retained in the oil layer for a somewhat longer time and this, because of their. low relation of weight to surface, is their natural tendency. They cannot, however, remain permanently in .the oil layer because, while it would be entirely feasible to separate them from the discharge oil and return them to the system, long continued contact with a mass of oil substantially free fromwater would cause them to become oil-wetted, in which condition they would be inert and nonfunctional as a reversing agent.

The fines must therefore be caused to pass continuously out of the oil layer into the water layer, where any adhering oil will be displaced and the full water-wetability of the solid particle restored, and from this layer the fines will subside as the above mentioned sludge. To produce this result the solids selected for the production of fines must have a higher adhesion tension with water than is requisite in the case of the coarse solids, in order to avoid their accumulation at the oil-water interface. Also, the apparatus must provide a liberal space of substantial quiescence in which the fine solids may work their way through the interface and in which free water may subside from the oil layer.

By observing the above precautions the final product of resolution may be continuously accumulated in the form of an upper layer of oil, more or less free from suspended water and residual emulsion (according to the extent to which the treatment is carried), an intermediate layer of water substantially free from oil and from fines, and a bottom layer of sludge carrying enough water to render it suited to pumping. From these three layers-the fines may be returned to the system, the water withdrawn and discarded and the oil directed to any suitable point for storage or use.

Where the emulsion under treatment contains a material proportion of earthy matter, shale or clay, this finely divided solid will become waterwetted if it is not already in such condition, will pass into the Water layer, and will finally form a fourth layer between the clear water and the top of the layer of sludge. Where this condition is known to exist in the emulsion, the fine solid chosen should be of the highest possible specific gravity in order that it may separate as completely as possible from the earthy matter in subsiding through the water layer.

A mere reversal of the terms of the above description will make it apply to the treatment of oil-in-water emulsions with solids lighter than oil, the solids in such case being withdrawn from the top of the oil layer and returned to the bottom of the water layer.

(7) Method of measuring adhesion tension rerelations Dry glass tubes of 3 to 6 mm. internal diameter (results are the same with various diameters) are closed'with cotton at'onel'end' and filled with powderedl'solids, then tappeduntiIthe powder settles no:mor.e; For: comparing various solids, it is important that all of: them be ground tothe same sizeiof particle, in order that capillary forcesbe equal: in: al1,xsince capillary attractions are related to the capillary diameters. Measurements mayrbe madewith powders passing an 80-1nesh screen, but retainedion a1100--mesh screen. These 1 powdersishouldrbe'washed thoroughly with water-c torremove fine dust, therrdried completely. When theatubes are filledwith the powders, they: are mountedvertically shallow containers for liquids; r When the liquid: comes :in contact with: i'tli'e -powder, it creeps upward, wetting the-powdenandsworksisidone in-lifting the liquid against theziforce of; gravity; The. height towhich the liquid: travels: up theicolumir of powder is measuredlinmillimeterst? Theclimbof liquidis rapid, immostrinstanees"; during the 'first few hours but continues more andimoreislowlyfor many days.

a The relative'adhesi'on itensions mentioned in the claimszarie inztermsiofsthe millimeters rise of the respective liqui'dsdn*powdersof. 80-to 100 mesh, in 2a'gb20xhours,.atordinary:roionttemperature.

l2 claimi'asi-myr invention lii'Ihe method of resolving an emulsionwhich" comprises: simultaneously and intimately contasting withwsaid emulsioma relatively:large quan- 1 .tity: of "a 'cearselyspowdered solid 1 and a relatively smalls quantity of 'ai finely: powdered" solid," both saidsolidsrbeing insoluble and chemically inert: to:alliconstituentsofisaidzemulsion andha'ving adhesion tension; with. theidispersed liquid not sub stantially'lessothana.2;5i time's 'th'e'inadh'esion ten sionrwitlr the; continuous? liquid of? said: emulsion andva .zspecific gravityvmaterially difierent from thatizofi said'iemul'siony ano'tso controlling the proportioniofi saidi fine'lz solidi in 1 said emulsion as" to producmresoluti'on. of i saidremulsion at'- a desired i 7 times their adhesiontension' with the'continuous rater r i r 2: The? method: of: resolving an emulsion-which comprises: simultaneously and intimately con tactingwith' 'said emulsion a relatively large quantity/of a; coarselyIpowdered solid having adhesion tension with. the dispersed liquid not less than' 1.5 =;times3litsaadhesiontension with the continu- I in'g a' a specific-t gravity materially different from 5a that1ofrsaid em ulsiomand Ase-controlling the proportion .iofssaid -fine solid said emulsion as to produceiresolution of said emulsion at adesired 3. The method of resolving an emulsion-which fimzcomprisesr simultaneously and intimately contactingwith said emulsion'a relatively large-"quantity: ofsasolid b'ody comminuted to be substantially retainedonalZ-mesh screenand a relativelysma-ll quantity of asolid loody eomminuted to substan-' 85 ing insoluble in and chemically-inert to all constituents ofis'aid emulsion and having adhesion tension with: the dispersed liquid substantially greatenthanstheir adhesion'tension with:- the con-- 7 ltinuous. liquid; and! so controlling the proportion oflz'said ifiner solidin said emulsion as -to produce resolutionlofsaid"emulsion at a desired rate.

4% The method- 0f resolving an emulsion which comprises: simultaneously and intimately-con tacting'with "said-emulsiona=relativelvlarge quangfWi-thlthef dispersedlliquid 1101? less than 2.5 times itia-lly pass adOO-meslr' scre'erifboth said soliolsloe in said emulsion asto produceresolution offsaid emulsion at a desired rate. r r

5. The method of resolving an e Zulsion when comprises: simultaneously and intimatel'y cdn tasting with said emulsion a relatively large' quan tity of a coarsely powdered solid having adhesion tensionW-ith tlie dispersed-liquid not less tha 5 times its adhesion tension with the. oontin us liquid and arelatively= small quantity of-a finel'y powdered solid produced by mutual abrasiofi o'f thegrains" of said coarsely powdered solid both said solids being insoluble in* and chemicallyinert to all consititlints of said emulsion and having a" 1 specific gravity materially different from that of said -einul'sion, and'so controlling the'prop'ortiori of said fine soliddn said emulsion as toproduce resolution of said-emulsion at a-desired ra'te'. v

'65 The method of resolving an oil-and-water' emulsion whichcomprises; simultaneously-and intimatelycontactingwith said'emulsion a relatively large quantity of a coarsely powdered solid and a' relatively smallquantity of a finely powdered solid, both said solids bein'giinsoluble in oi1ia'n"d waterr-andi chemically: inert'to" all constituents of: said emulsion and having adhesion tension'withi the dispersed"liquidnot substantially less than.2.5 40' liquid":and="aaspecific gravity materially different from that ot'said emulsion, and so controlling'the proportionvoffsaid fine'solid in'said iemulsionias to 1 produce: resolutionof said emulsionxat a desired rate? i 7.1 The" method of resolving an oil-andewater emulsion: which comprises: simultaneously and intimately 'contacting'with said-'Lemuls'ion" a relatively largeiquantity of a'zcoarsely' powderedtsolid 5d" havingtadliesion tension zwith' thedispersedrliquid 7 not: lessrthan 1.5 .timesiits adhesion tension with thercontinuous liquid; and ra relatively small quantity. of a: finely powdered .solidihavingr adhesion tension with the dispersed liquid notwless thari 215' times" its adhesioni tension" with the" continuous liquid, botlrasaid ssolids lbeingr'insoluble in oil and:

water'randichemically inert to all constituentsrrof saidziemulsion and having a specific'gravityinate= t riallyidifierent from that of: said emulsion, and so controllingthe proportion'iof'isaid fine-solidinsitid emulsion as toproduce'resolution'ofsaid emulsion at a desired.v rate.

.8.-: The; method: of resolving an oil-andewatersi' emulsion .which' comprises: simultaneously andzt intimately contacting with said emulsion-a relattivelylarge'quantity'of azsolid body comminuted i to be substantially retained on a l2-mes'li scree'ri andh'aving an adhesion tension with thedisr'iersedliquid not lessthan 1,5 times-its adhesion tension with; the 'continuous liquid, anda relatively small quantity of a 1 solid body'comminuted tosubstantially-pass a 1Q0- mesh sereen and having-an ad 'hesion' tension with thedispersed liquid not less than-'zefitimes its adhesiontension-with the-"continuous liquid, both said solids being insoluble in oil and water and chemically inert to all constituents of said emulsion and having a specific gravity less than that of the oil constituent of the emulsion or greater than that of water, and so controlling the proportion of said fine solid in said emulsion as to produce resolution of said emulsion at a desired rate.

9. The method of resolving an oil-and-water emulsion which comprises: simultaneously and intimately contacting with said emulsion a relatively large quantity of a coarsely powdered solid having adhesion tension with the dispersed liquid not less than 1.5 times its adhesion tension with the continuous liquidand a relatively small quantity of a finely powdered solid produced by mutual abrasion of the grains of said coarsely powdered solid, both said solids being insoluble in oil and water and chemically inert to all constituents of said emulsion and having a specific gravity materially dilferent from that of said emulsion, and so controlling the proportion of said fine solid in said emulsion as to produce resolution of said emulsion at a desired rate.

10. The method of resolving an oil-in-water emulsion which comprises: simultaneously and intimately contacting with said emulsion a relatively large quantity of a coarsely powdered solid and a relatively small quantity of a finely powdered solid, both said solids being insoluble in oil and water and chemically inert to all constituents of said emulsion and having adhesion tension with oil not substantially less than 2.5 times their adhesion tension with water and having a specific gravity materially less than that of the oil constituent of said emulsion, and so controlling the proportion of said fine solid in said emulsion as to produce resolution of said emulsion at a desired rate.

11. The method of resolving an oil-in-water emulsion which comprises: simultaneously and intimately contacting with said emulsion a relatively large quantity of a coarsely powdered solid having adhesion tension with oil not less than 1.5 times its adhesion tension with water and a relatively small quantity of a finely powdered solid having adhesion tension with oil not less than 2.5 times its adhesion tension with water, both said solids being insoluble in oil andvwater and chemi-;

, cally inert to all constituents of said emulsion and having a specific gravity materially less than that of the oil constituent of said emulsion, and so controlling the proportion of said fine solid in said emulsion as to produce resolution of said emulsion at a desired rate.

12. The method of resolving an oil-in-water emulsion which comprises: simultaneously and intimately contacting with said emulsion a relatively large quantity of a solid body comminuted to be substantially retained on a 12-mesh screen.

and having an adhesion tension with the dispersed liquid not less than 1.5 times its adhesion tension with the continuous liquid, and a relatively small quantity of a solid body comminuted to substantially pass a 100-mesh screen and having an adhesion tension with the dispersed liquid not lessv than 2.5 times its adhesion tension with the continuous liquid, both said solids being insoluble in oil and water and chemically inert to all constitucuts of said emulsion and having a specific gravity materially less than that of the oil constituentof said emulsion, and so controlling the proportion of said fine solid in said emulsion as to produce resolution of said emulsion at a desired rate.

13. The method of resolving an oil-in-water emulsion, which. comprises: simultaneously and intimately contacting with said emulsion a relatively large quantity of .a coarsely powdered solid having adhesion tension with oil not less than 1.5 times its adhesion tension with water and a relatively small quantity of a finely powdered solid produced by mutual abrasion of the grains of saidv coarsely powdered solid, both said solids being insoluble in oil and water and chemically inert to all constituents of said emulsion and having a specific gravity materially less than that of the oil constituent of said emulsion, and so controlling the proportion of fines in said emulsion as to produce resolution of said emulsion at a desired'ra'te.v

14. The method of resolving a water-in-oil emulsion which comprises: simultaneously and intimately contacting with said emulsion a relatively large quantity of a coarsely powdered solid and a relatively small quantity of a finely powdered solid, both said solids being insoluble in water and oil and chemically inert to all constituents of said emulsion and having adhesion tension with water not substantially less than 2.5 times their adhesion tension with oil and having a specific gravity materially greater than that of Water, and so controlling the proportion of said fine solid in said emulsion as to produce resolution of said emulsion at a desired rate.

15. The method of resolving a water-in-oil emulsion which comprises: simultaneously and intimately contacting with said emulsion a relatively large quantity of a coarsely powdered solid having adhesion tension with water not less than 1.5 times its adhesion tension with oil and a relatively small quantity of a finely powdered solid having adhesion tension with water not less than 2.5 times its adhesion tension with oil, both said solids being insoluble in water and oil and chemically inert to all constituents of said emulsion and having a specific gravity materially greater than that of water, and so controlling the proportion of said fine solid in said emulsion as to produce resolution of said emulsion at adesir'ed rate.

16. The method of resolving a water-in-oil emulsion which comprises: simultaneously and intimately contacting with said emulsiona relatively large quantity of a solid body comminuted to be substantially retained on a 12-mesh screen and a relatively small quantity of a solid body comminuted to substantially pass a loo-mesh screen, both said solids being insoluble in water and oil and chemically inert to all constituents of said emulsion'and having adhesion tension with water not substantially less than 2.5 times their adhesion tension with oil and having a specific gravity materially greater than that of water, and so controlling the proportion of said fine solid in said emulsion as to produce resolution of said emulsion at a desired rate.

17. The method of resolving a water-in-oil emulsion which comprises: simultaneously and;

intimately contacting with said emulsion a relatively large :quantity of a solid body comminuted,

to be substantially retained on a 12-mesh screen and having an adhesion tension with the dispersed liquid not less than 1.5 times its adhesion tension with the continuous liquid, and a relatively small quantity of a solid body comminuted to substantially pass a loo-mesh screen and having an adhesion tension with the dispersed liquid not less than 2.5 times its adhesion tension with, the continuous liquid, both said solids being insoluble in water-and oil and chemically inert to all constituents of said emulsion and having a specific gravity materially greater thanthat of water,

and so controlling the proportion of said fine solid in said emulsion as to produce resolution of said emulsion at a desired rate.

18. The method of resolving a water-in-oil emulsion which comprises: simultaneously and intimately contacting with said emulsion a relatively large quantity of a coarsely powdered solid having adhesion tension with Water not less than 1.5 times its adhesion tension with oil and a rela- 10 tively small quantity of a finely powdered solid produced by mutual abrasion of the grains of said coarsely powdered solid, both said solids being insoluble in oil and water and chemically inert to all constituents of said emulsion and having a specific gravity materially greater than that of water, and so controlling the proportion of said fine solid in said emulsion as to produce resolution of said emulsion at a desired rate. 

